scholarly journals Forest canopy resists plant invasions: a case study of Chromolaena odorata in sub-tropical Sal (Shorea robusta) forests of Nepal

2019 ◽  
Author(s):  
LN Sharma ◽  
B Adhikari ◽  
MF Watson ◽  
B Karna ◽  
E Paudel ◽  
...  
Keyword(s):  
Invasive Species ◽  
Forest Canopy ◽  
Management Practices ◽  
Forest Ecosystems ◽  
Canopy Cover ◽  
Economic Damage ◽  
Specific Information ◽  
Shrub Cover ◽  
Chromolaena Odorata ◽  
Shorea Robusta

AbstractInvasive Alien Species cause tremendous ecological and economic damage in agriculture, forestry, aquatic ecosystems, and pastoral resources. They are one of the major threats to biodiversity conservation. Understanding the spatial pattern of invasive species and disentangling the biophysical drivers of invasion at forest stand level is essential for managing invasive species in forest ecosystems and the wider landscape. However, forest-level and species-specific information on invasive species abundance and area of extent is largely lacking. In this context, we analysed the cover of one of the world’s worst invasive plant species Chromolaena odorata in Sal (Shorea robusta Gaertn.) forest in central Nepal. Vegetation was sampled in four community-managed forests using 0.01 ha square quadrats, covering forest edge to the interior. Chromolaena cover, floral richness, tree density, forest canopy cover, shrub cover, and tree basal area were measured in each plot. We also estimated the level of disturbance in plots, and calculated distance from the plot to the nearest road. We also explored forest and invasive species management practices in community forests.Chromolaena cover was found to be negatively correlated with forest canopy cover, distance to the nearest road, angle of slope and shrub cover. Canopy cover had the greatest effect on the Chromolaena cover. Chromolaena cover did not show any pattern along native species richness gradients. In conclusion, forest canopy cover is the overriding biotic covariate affecting Chromolaena cover in Sal forests. The practical application of our results in managing Chromolaena in forest ecosystems is discussed.

Forest canopy resists plant invasions: a case study of Chromolaena odorata in Sal (Shorea robusta) forests of Nepal

2022 ◽  
pp. 1-9
Author(s):  
L. N. Sharma ◽  
B. Adhikari ◽  
M. F. Watson ◽  
B. B. Shrestha ◽  
E. Paudel ◽  
...  
Keyword(s):  
Alien Species ◽  
Forest Canopy ◽  
Invasive Alien Species ◽  
Canopy Cover ◽  
Economic Damage ◽  
Shrub Cover ◽  
Chromolaena Odorata ◽  
Alien Plant ◽  
Community Forests ◽  
Shorea Robusta

Abstract Invasive alien species are a major threat to global biodiversity due to the tremendous ecological and economic damage they cause in forestry, agriculture, wetlands, and pastoral resources. Understanding the spatial pattern of invasive alien species and disentangling the biophysical drivers of invasion at the forest stand level is essential for managing forest ecosystems and the wider landscape. However, forest-level and species-specific information on Invasive Alien Plant Species (IAPS) abundance and their spatial extent are largely lacking. In this context, we analysed the cover of one of the world’s worst invasive plants, Chromolaena odorata, in Sal (Shorea robusta) forest in central Nepal. Vegetation was sampled in four community forests using 0.01 ha square quadrats, covering the forest edge to the interior. C. odorata cover, floral richness, tree density, forest canopy cover, shrub cover, tree basal area, and disturbances were measured in each plot. We also explored forest and IAPS management practices in community forests. C. odorata cover was negatively correlated with forest canopy cover, distance to the road, angle of slope, and shrub cover. Tree canopy cover had the largest effect on C. odorata cover. No pattern of C. odorata cover was seen along native species richness gradients. In conclusion, forest canopy cover is the overriding biotic covariate suppressing C. odorata cover in Sal forests.

scholarly journals Morphological plasticity of corms in enhancing invasion of Chromolaena odorata

2013 ◽  
Vol 21 (2) ◽  
pp. 3-12
Author(s):  
C. Joshi ◽  
J. Van Andel ◽  
A. Skidmore ◽  
J. De Leeuw ◽  
I. V. Duren
Keyword(s):  
Forest Canopy ◽  
Morphological Plasticity ◽  
Invasion Success ◽  
Chromolaena Odorata ◽  
Canopy Density ◽  
Shorea Robusta ◽  
South Central ◽  
Light Gradient ◽  
Forest Canopy Density ◽  
Closed Canopy

In this paper, the researchers investigate the vegetative growth of Chromolaena odorata and the infl uence of light intensity on the understorey environment of Shorea robusta forest at Chitwan in south-central Terai, Nepal. C. odorata is a clonally growing shrub and typically consists of several clones with an underground “cormous organ” (a modifi ed stem to store food reserve; here after “corm”) belonging to an identical genet. In C. odorata, the biomass of such corms varied across the light gradient. The number of shoot demonstrated a strong logarithmic relation with biomass of corm. Under open forest canopy environment, corm biomass was strongly correlated with the number of shoots and the corm’s age. However, under dense forest canopy, there was no signifi cant relationship between corm biomass and its age. This result shows that corms of C. odorata were capable of maintaining their viability for a long period even under closed canopy environment. Any disturbances in forest canopy density would ultimately trigger its clonal growth capability. This plasticity of corms appeared to be a key strategy for invasion success of this species. Comparison of these results further indicates the importance of canopy density in determining invasion success of C. odorata.DOI: http://dx.doi.org/10.3126/banko.v21i2.9124Banko JanakariVol. 21, No. 2, 2011Page: 3-12Uploaded date: November 10, 2013 

Invasive Shot Hole Borers Euwallacea fornicatus, E. kuroshio, and E. perbrevis (Coleoptera: Curculionidae: Scolytinae)

EDIS ◽  
2020 ◽  
Vol 2020 (1) ◽  
pp. 7
Author(s):  
Demian F. Gomez ◽  
Jiri Hulcr ◽  
Daniel Carrillo
Keyword(s):  
South Africa ◽  
Invasive Species ◽  
Prevention And Control ◽  
Economic Impacts ◽  
Forest Resources ◽  
Economic Damage ◽  
Ambrosia Beetles ◽  
Invasive Insects ◽  
The World ◽  
And Control

Invasive species, those that are nonnative and cause economic damage, are one of the main threats to ecosystems around the world. Ambrosia beetles are some of the most common invasive insects. Currently, severe economic impacts have been increasingly reported for all the invasive shot hole borers in South Africa, California, Israel, and throughout Asia. This 7-page fact sheet written by Demian F. Gomez, Jiri Hulcr, and Daniel Carrillo and published by the School of Forest Resources and Conservation describes shot hole borers and their biology and hosts and lists some strategies for prevention and control of these pests. http://edis.ifas.ufl.edu/fr422

scholarly journals Individual and Combined Effects of Planting Date, Seeding Rate, Relative Maturity, and Row Spacing on Soybean Yield

Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 605
Author(s):  
Peder K. Schmitz ◽  
Hans J. Kandel
Keyword(s):  
Seed Yield ◽  
Management Practices ◽  
Synergistic Effects ◽  
Canopy Cover ◽  
Planting Date ◽  
Row Spacing ◽  
Growth Stages ◽  
Seeding Rate ◽  
Yield Increase ◽  
Beginning Of Flowering

Planting date (PD), seeding rate (SR), relative maturity (RM) of cultivars, and row spacing (RS) are primary management factors affecting soybean (Glycine max (L.) Merr.) yield. The individual and synergistic effects of PD, SR, RM, and RS on seed yield and agronomic characteristics in North Dakota were herein investigated. Early and late PD, early and late RM cultivars, two SR (408,000 and 457,000 seed ha−1), and two RS (30.5 and 61 cm) were evaluated in four total environments in 2019 and 2020. Maximizing green canopy cover prior to the beginning of flowering improved seed yield. Individual factors of early PD and narrow RS resulted in yield increase of 311 and 266 kg ha−1, respectively. The combined factors of early PD, late RM, high SR, and narrow RS improved yield by 26% and provided a $350 ha−1 partial profit over conventional practices. Canopy cover and yield had relatively weak relationships with r2 of 0.36, 0.23, 0.14, and 0.21 at the two trifoliolate, four trifoliolate, beginning of flowering, and beginning of pod formation soybean growth stages, respectively. Producers in the most northern soybean region of the USA should combine early planting, optimum RM cultivars, 457,000 seed ha−1 SR, and 31 cm RS to improve yield and profit compared to current management practices.

Distribution and habitat preference of protected reindeer lichen species (Cladonia arbuscula, C. mitis and C. rangiferina) in the Balaton Uplands (Hungary)

2021 ◽  
Vol 53 (3) ◽  
pp. 271-282
Author(s):  
Mónika Sinigla ◽  
Erzsébet Szurdoki ◽  
László Lőkös ◽  
Dénes Bartha ◽  
István Galambos ◽  
...  
Keyword(s):  
Vascular Plants ◽  
Management Practices ◽  
Soil Depth ◽  
Habitat Preferences ◽  
Habitat Type ◽  
Canopy Cover ◽  
Lichen Species ◽  
Oak Forests ◽  
Natural Habitats ◽  
Cladonia Rangiferina

AbstractThe maintenance of protected lichen species and their biodiversity in general depends on good management practices based on their distribution and habitat preferences. To date, 10 of the 17 protected lichen species of Hungary have been recorded in the Bakony Mts including the Balaton Uplands region. Habitat preferences of three protected Cladonia species (C. arbuscula, C. mitis and C. rangiferina) growing on underlying rocks of red sandstone, basalt, Pannonian sandstone and gravel were investigated by detailed sampling. We recorded aspect, underlying rock type, soil depth, pH and CaCO3 content, habitat type (as defined by the General National Habitat Classification System Á-NÉR), all species of lichen, bryophyte and vascular plants as well as percentage cover of exposed rock, total bryophytes, lichens, vascular plants and canopy, degree of disturbance and animal impacts. Sporadic populations of these species mostly exist at the top of hills and mountains in open acidofrequent oak forests, but they may occur in other habitats, such as closed acidofrequent oak forests, slope steppes on stony soils, siliceous open rocky grasslands, open sand steppes, wet and mesic pioneer scrub and dry Calluna heaths. Cladonia rangiferina was found to grow beneath higher canopy cover than either C. arbuscula or C. mitis in the Balaton Uplands. Furthermore, there were significant differences in canopy cover between occupied and unoccupied quadrats in the case of all three species. Cladonia rangiferina is a good indicator species of natural habitats in Hungary due to its restricted distribution and low ecological tolerance. These results may lead to the adoption of effective conservation methods (e.g. game exclusion, artificial dispersal) in the future.

scholarly journals Estimating Forest Canopy Cover by Multiscale Remote Sensing in Northeast Jiangxi, China

Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 433
Author(s):  
Xiaolan Huang ◽  
Weicheng Wu ◽  
Tingting Shen ◽  
Lifeng Xie ◽  
Yaozu Qin ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Large Scale ◽  
Forest Canopy ◽  
Canopy Cover ◽  
Google Earth ◽  
Tree Canopy ◽  
Landsat Data ◽  
High Resolution Data ◽  
Modis Ndvi ◽  
Tree Canopy Cover

This research was focused on estimation of tree canopy cover (CC) by multiscale remote sensing in south China. The key aim is to establish the relationship between CC and woody NDVI (NDVIW) or to build a CC-NDVIW model taking northeast Jiangxi as an example. Based on field CC measurements, this research used Google Earth as a complementary source to measure CC. In total, 63 sample plots of CC were created, among which 45 were applied for modeling and the remaining 18 were employed for verification. In order to ascertain the ratio R of NDVIW to the satellite observed NDVI, a 20-year time-series MODIS NDVI dataset was utilized for decomposition to obtain the NDVIW component, and then the ratio R was calculated with the equation R = (NDVIW/NDVI) *100%, respectively, for forest (CC >60%), medium woodland (CC = 25–60%) and sparse woodland (CC 1–25%). Landsat TM and OLI images that had been orthorectified by the provider USGS were atmospherically corrected using the COST model and used to derive NDVIL. R was multiplied for the NDVIL image to extract the woody NDVI (NDVIWL) from Landsat data for each of these plots. The 45 plots of CC data were linearly fitted to the NDVIWL, and a model with CC = 103.843 NDVIW + 6.157 (R2 = 0.881) was obtained. This equation was applied to predict CC at the 18 verification plots and a good agreement was found (R2 = 0.897). This validated CC-NDVIW model was further applied to the woody NDVI of forest, medium woodland and sparse woodland derived from Landsat data for regional CC estimation. An independent group of 24 measured plots was utilized for validation of the results, and an accuracy of 83.0% was obtained. Thence, the developed model has high predictivity and is suitable for large-scale estimation of CC using high-resolution data.

Forest canopy cover analysis using UAS lidar

2017 ◽  
Author(s):  
Qingwang Liu ◽  
Shiming Li ◽  
Kailong Hu ◽  
Yong Pang ◽  
Zengyuan Li
Keyword(s):  
Forest Canopy ◽  
Canopy Cover

Initial dispersal behavior and survival of non-native juvenile Burmese pythons (Python bivittatus) in South Florida

BMC Zoology ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Shannon E. Pittman ◽  
Ian A. Bartoszek
Keyword(s):  
Invasive Species ◽  
Management Practices ◽  
South Florida ◽  
Movement Behavior ◽  
Forested Wetland ◽  
Common Source ◽  
Vital Rates ◽  
Natural Habitats ◽  
Dispersal Behavior ◽  
Python Bivittatus

Abstract Background Dispersal behavior is a critical component of invasive species dynamics, impacting both spatial spread and population density. In South Florida, Burmese pythons (Python bivittatus) are an invasive species that disrupt ecosystems and have the potential to expand their range northward. Control of python populations is limited by a lack of information on movement behavior and vital rates, especially within the younger age classes. We radio-tracked 28 Burmese pythons from hatching until natural mortality for approximately 3 years. Pythons were chosen from 4 clutches deposited by adult females in 4 different habitats: forested wetland, urban interface, upland pine, and agricultural interface. Results Known-fate survival estimate was 35.7% (95% CI = 18% - 53%) in the first 6 months, and only 2 snakes survived 3 years post hatching. Snakes moving through ‘natural’ habitats had higher survival than snakes dispersing through ‘modified’ habitats in the first 6- months post-hatching. Predation was the most common source of mortality. Snakes from the agricultural interface utilized canals and displayed the largest net movements. Conclusions Our results suggest that pythons may have lower survival if clutches are deposited in or near urbanized areas. Alternatively, juvenile pythons could quickly disperse to new locations by utilizing canals that facilitate linear movement. This study provides critical information about behavioral and life history characteristics of juvenile Burmese pythons that will inform management practices.

scholarly journals DNA-based species detection capabilities using laser transmission spectroscopy

2013 ◽  
Vol 10 (78) ◽  
pp. 20120637 ◽  
Author(s):  
A. R. Mahon ◽  
M. A. Barnes ◽  
F. Li ◽  
S. P. Egan ◽  
C. E. Tanner ◽  
...  
Keyword(s):  
Invasive Species ◽  
Dna Detection ◽  
Field Application ◽  
Economic Damage ◽  
Oligonucleotide Probes ◽  
Target Species ◽  
Dreissena Bugensis ◽  
Species Detection ◽  
Transmission Spectroscopy ◽  
Species Specific

Early detection of invasive species is critical for effective biocontrol to mitigate potential ecological and economic damage. Laser transmission spectroscopy (LTS) is a powerful solution offering real-time, DNA-based species detection in the field. LTS can measure the size, shape and number of nanoparticles in a solution and was used here to detect size shifts resulting from hybridization of the polymerase chain reaction product to nanoparticles functionalized with species-specific oligonucleotide probes or with the species-specific oligonucleotide probes alone. We carried out a series of DNA detection experiments using the invasive freshwater quagga mussel ( Dreissena bugensis ) to evaluate the capability of the LTS platform for invasive species detection. Specifically, we tested LTS sensitivity to (i) DNA concentrations of a single target species, (ii) the presence of a target species within a mixed sample of other closely related species, (iii) species-specific functionalized nanoparticles versus species-specific oligonucleotide probes alone, and (iv) amplified DNA fragments versus unamplified genomic DNA. We demonstrate that LTS is a highly sensitive technique for rapid target species detection, with detection limits in the picomolar range, capable of successful identification in multispecies samples containing target and non-target species DNA. These results indicate that the LTS DNA detection platform will be useful for field application of target species. Additionally, we find that LTS detection is effective with species-specific oligonucleotide tags alone or when they are attached to polystyrene nanobeads and with both amplified and unamplified DNA, indicating that the technique may also have versatility for broader applications.

Sign in / Sign up

Export Citation Format

Share Document